Second Longest Possible Palindrome
(Published on 11. June 2020, 12:48 by stephane.bura)
If you're looking for the longest possible palindrome, it's in this puzzle
Normal Sudoku rules apply.
The gray line is a palindrome so, for instance, the digit in R2C5 is the same as the one in R3C2.
When the palindrome exits the grid, it continues on the opposite side (from R1C1 to R9C1 and from R4C1 to R4C9).
The dotted rectangles contain digits that add up to 15.
The three dotted circles also contain digits that add up to 15.
Penpa-Edit link for this puzzle to play it online.
Solution code: Row 5, column 5
Comments
on 8. September 2020, 20:18 by luda3
Wonderful palindrome sudoku puzzle, thank you for sharing
on 13. June 2020, 17:57 by glum_hippo
@dm_litv 'Endless, senseless flood of pseudo-puzzles' - what a charming comment.
on 13. June 2020, 12:33 by stephane.bura
Changed the title and added the link to the new puzzle.
on 12. June 2020, 00:47 by Madmahogany
Nice one! Very pretty
on 11. June 2020, 23:13 by dm_litv
Ah, sorry. Maybe I was wrong.
But right now I don't see clear prove of the impossibility to make 73.
I have to think about it. At least it's an interesting problem among the endless senseless flood of pseudo-puzzles here recently ;(
on 11. June 2020, 20:35 by Greg
Really enjoyed it.
And now looking forward to the longest palindrome plus 1
on 11. June 2020, 20:13 by stephane.bura
I don't know if it's possible to add a digit in the center of the palindrome. Someone please show me!
Until then, I'll keep this title ;)
on 11. June 2020, 19:56 by stephane.bura
@dm_litv but you're right! There could be one more digit at the center of the palindrome. It was just brain taxing enough to design this with the help of symmetries ;)
on 11. June 2020, 19:39 by dm_litv
Evidently it's not the longest.
on 11. June 2020, 14:48 by KeyserSoze
Enjoyable quick puzzle. Thanks
